image sequence offset

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Hello!
Is there a way to offset an image sequence so that every geo uses the same texture sequence, but has a different start point? I've tried using copy sop and timeshift, but wasn't able to make it work. Any tips/ideas would be greatly appreciated. Thank you!

Jason
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If your using a copy sop something like

$HIP/texture/myimage_sequence_`padzero(4,$F + stamp(“../copy1”,“offset”,0))`.exr

Then in your copy sop your “offset” will be your rand start frame.

Rob
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Thank you for the reply, circusmonkey! That was the first thing I've tried actually, but surprisingly it didn't work. Interesting thing is that the same method works when it comes to bgeo sequence, but not with image sequence. Not sure why it wouldn't work.
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I don't think the stamp function can be evaluated at rendertime, can it? It would have to be cooked in the sop level prior to sending it to Mantra, hence the pointcloud workarounds and such.
What you might be able to do is create a point attribute on your geo with the offset values. and load that attribute in your shader and do the offsetting of texture value within it.

Cheers
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Thanks for the tip, Rafael! I have some follow up questions for you. I created an attribute that spits out a random frame number per point, but how would I integrate the attribute into the shader file path, so that each copy has a different start frame number without using a stamp expression? Hopefully I am making sense. Thanks again for your help!
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Check the attached file. First you'll have to render the images sequence in COP and then try to render the scene.

Cheers

Attachments:
offset_textures.hip (225.3 KB)

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Interesting. Guess if I had opened up Houdini and tested it …..

I must admit I would of made a vop sop and created a simple attribute that counts using $F and then assigned a random start frame per point. Each copy then would pick up the newly created Variable. Then further down the tree in a material sop I would create an override for the texture and use my new variable as the random start point ! . hope that makes sense

Rob
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yeah, guess my method was a bit convoluted, but then I just wanted to prove the point anyway. It's surely not the most efficient way
Plus I had no idea you can't cast a variable to type string in VEX or VOP, am I crazy?!?
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Thank you all for your help! Unfortunately my studio only allows me to use h11, and couldn't make your file to work properly.
Rob's idea is also interesting. Hopefully I can make one of them work.
Thanks again!!
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The workflow I used should be work just fine in H11.
if you can take a look at it later from your home computer I'm sure you can reproduce it in H11.

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Jason Kim
Thank you all for your help! Unfortunately my studio only allows me to use h11, and couldn't make your file to work properly.
Rob's idea is also interesting. Hopefully I can make one of them work.
Thanks again!!

My idea would work in H11

Rob
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